Damage assessment of two-layer targets under nominal ordnance impact

Perforation and penetration of two-layer targets composed of aluminum and steel by a taper-nosed projectile is investigated. The proposed method in analysing the present study is based upon the energy density damage theory. Both aluminum and steel are modeled as elastic/plastic materials which were used as the based materials at the beginning of penetration process. After the target is damaged, the behavior of material elements in the target varies from one location to another depending on local strain rates which were derived in the energy desity damage theory. An initial velocity of 1300 m/sec of the projectile made of tungsten is considered to thrust through the targets with aluminum/steel and steel/aluminum layered systems. The complete time history of damage until the targets were broken in two has been obtained and provided in graphic form. The reults presented in this work will be helpful in deep understanding of penetration process.